Terrible service and food

Good day, I'm at one of your burger King branches in Centurion. I ordered and went to the bathroom when one of the employees came out of a stall and did not wash their hands. Now their handling food like that. When I went to tell the manager they said there is nothing they can do and they won't return our money. Really not okay. After everything, we got the wrong food. We ordered chicken burgers and we got beef. The milkshake was watery. We order EVERY Thursday. This was the last time